Adding it up: Lisa's September to November 2001 bill for 600 units of electricity

London Electricity �45.88 Scottish Hydro Electric �39.86 Atlantic Electric and Gas �45.36 Amerada �40.50 Amerada Online �41.30 British Gas �50.17

Like the car insurance I paid for a year after said car had been towed away for �20 to a scrap yard with plants growing out of it because I hadn't used it for so long.

Financially savvy I am not but it appears I am not alone.

The consumers' watchdog Which? says that inertia and confusion stop millions of us making savings on our utility bills.

It also says that 90% of people who did switch providers found it "easy".

So how do you start?

The Which? website is packed with useful tips, including a survey of the best and worst utility companies.

How to do it

It also has links to sites which will compare prices for you.

I used www.uswitch.co.uk

The first thing that stunned me was my choice of supplier.

There were 17 to choose from offering 31 different schemes.

I filled in the amount of my last quarterly bill with my current provider London Electricity - �45.88 - and a computer programme did the rest.

Consumers can choose from many companies

According to uswitch, I could be saving 10%, or �17.80, a year by switching to Atlantic Electric and Gas.

It listed other providers, how much they could save me and an option to switch to them.

Ever cautious, I decided to ring a selection of the companies suggested by uswitch to compare their charges.

All you need to know is what kind of meter you are on - standard or Economy 7 - the number of units of electricity you use per month and how you pay. All these details are on your existing bill.

Then you need just two numbers to work out how different companies compare - the standing charge and price per unit.

Within about half an hour I had spoken to four companies, looked up one online option and worked out how my quarterly bills compared.

No degree needed

Edward Leigh MP, chairman of the House of Commons public accounts committee which investigated how easy it is to switch, said consumers need a maths degree to work out which company is best for them.

But it really is not that hard. I used a calculator and even with my aversion to numbers, the maths involved was very straightforward.

You just have to make sure you are comparing like with like. Some providers give discounts if you pay by direct debit and others do not ask for a standing charge.

In the end, Scottish Hydro Electric offered me the best saving at �39.86 for my November bill, compared to the �45.88 London Electricity is charging.

I rang them back and told them I want to switch.

I will get a seven days "cooling off" period after I have signed the contract and then they will contact London Electricity and arrange the change. I don't have to do any more.

Don't be fobbed off

The only time I have thought (briefly) about switching before was when a British Gas salesman knocked on my door out of the blue.

Apart from objecting to the cold calling technique, that old inertia kicked in so I did nothing about it.

The company was not in my top five cheapest deals identified by uswitch but I decided to give them a try anyway.

The operator I spoke to told me that for an average bill of �260, the saving of moving from London Electricity would be 6%.

I pressed her for the exact unit costs and my November bill would work out at �50.17 - �27.16 more a year than I am already paying.

So the message is don't be fobbed off by promises of savings. Just make some time, get your calculator out and don't be scared.